My computer is connected to an external drive that has Time Machine on it. If I remove all of the files from the computer and then connect my Time Machine external hard drive to it can I reinstall all of the files from Time Machine? The answer is yes I'm sure, but will those files then be replaced in a nice and tightly packaged manner instead of being strewn all over the hard drive? What I'm getting at is will this work like a defragmenting process on Windows?

If I copy all of the files onto a different external hard drive for safety, then move the files on the Mac to the trash and click on Empty Securely, won't that be like starting from scratch, thus the restored files from Time Machine will be replaced in a more compact way?

I bought a secondary external hard drive for the just in case scenario if my Time Machine fails. I even have a Carbon Copy Cloner working. My main goal is to see if I can get my computer to work a little faster. It is getting a bit slow with the pinwheel spinning more often than it did when it was new.

I would rather not go into using Carbon Copy Cloner because using that requires wiping everything. I would rather just focus on the files, not the programs.

I've never seen a need to defrag a mac hard drive. You deon't really get the same issues as you do with Windows.

More important I think is how full the drive is. How big is your HDD and how much space do you have on it ?

The way I have done mine in the past is to create a full clone backup using Carbon Copy Cloner / Superduper etc. Then reinstall the OS on the original drive and start from a clean slate. Restoring only what you need from the backup. I've really only done this when installing a new OS. Like jumping from Snow Leopard to Lion and such.

I also use Chronosync to backup the important files to multiple backups. examples being my iTunes library, Pictures folder, Documents, Dropbox I create individual backup jobs for each major folder structure and back them up individually._________________Phil

A Mac running any version of OS X later than 10.2 does not need to be defragmented. OS X has its own built-in safeguards that prevent files from becoming fragmented in the first place.

OS X’s HFS+ file system tries not to use recently freed file space on a disk. Instead, it looks for larger free areas already present on the drive, thereby avoiding fragmenting files just to fit them into available space.

OS X dynamically gathers groups of small files and combines them into larger areas on your disk automatically. The process of writing the files to a new larger location defragments all of the files in the group.

OS X implements Hot File Adaptive Clustering, which monitors frequently-accessed files that do not get changed (read only), and then moves these often-accessed files to a special hot zone on the hard drive. In the process of moving these files, OS X defragments them, and then stores them in the area of the hard drive that has the fastest access.

When you open a file, OS X checks to see if it is highly fragmented (more than 8 fragments). If it is, OS X will automatically defragment the file.

According Apple's advice, there are two scenarios under which you might need to defragment your drive:

Since my machine has about half of the hard drive full and the OSX operating system automatically defragments the hard drive, then my machine should be running just as fast as the day I bought it. There must be more to it than that. The amount of files on the hard drive must play a big role in the speed of the computer doing operations involving the hard drive, even with much less than 90% occupied. If it didn't then why are people so impressed with solid state drives? Clearly they find and serve data faster because they don't need to wait for the platter and arm to align.

I keep the Activity Monitor running in the dock where I can see the CPU activity. There is always a lot of red on the bottom when doing things like viewing slide shows in the Firefox browser. Moving files around I get a lot of it too. It seems that whenever graphical actions are happening there is a lot of red under the green. This always corresponds with the machine going slower. It is at these times when the pinwheel shows itself. When the machine was new I didn't use this feature so I can't compare the behavior on the graph today to what happened then. I just know that I get the pinwheel a lot more these days than I ever did in the first three years of owning this machine.

I remember seeing videos on Youtube about the spinning pinwheel some people would get. Mostly they were on videos of people complaining about their Macs. I remember thinking that I had only seen the pinwheel a couple of times at the most. Now I see it many times per day.

When I finish using a program I quit it. I don't let it keep running in the background. The only one I will let stay on for a while is Chrome. There are sites where I view slide shows. Using Firefox on those sites is really slow. I open the Chrome browser and view the slide shows much faster. If I have a problem with viewing a video with Firefox I try it in Chrome. Most of the time it will work. When I'm just visiting sites like this one I will quit Chrome.

So if I were to clean out the files and reload them would the computer arrange them so that all of the data of each file was together? Would it place all of the reloaded files into a more compact space? Even if they were already defragmented as individual files wouldn't the machine do better if all of the files were closer together?

My iMac came with Tiger, since then I have upgraded to Leopard, Snow Leopard, Lion, Mountain Lion. I doubt it will be running anything like as quick as it would if I put Tiger back on.

The OS and modern apps will require more resources than the older versions so its inevitable that it will slow down.

I did notice my iMac was getting slower over several months till eventually I put it down to a failing HDD. I bought a new 1TB hard drive where previously it was a 250GB. That definitely got mine back up to some sort of normal operation again.

I also have a Mini and I would even say my iMac has always been quicker than my higher spec'd Mac Mini. The mini is a 2.53GHz Core 2 Duo, the iMac only a 2.0Ghz Core 2 Duo both have 4GB Ram. The iMac is the much faster machine. The mini feels sluggish compared to the iMac. Certainly when it comes to start up and starting big programs. I guess its the slower 2.5" HDD in the mini thats to blame. However I think its more noticeable nowadays with the newer OS's. the Mini really struggled on Lion and is slightly better now with Mountain Lion but its rarely turned on nowadays as I prefer to use the iMac.

How much free ram do you have ?

Maybe its time to put in a larger capacity / faster HDD_________________Phil

The computer is a late 2008 2.4 GHz Core 2 Duo with 2 GB RAM. It is running 10.5.8 Leopard. I don't want to upgrade the OS. The hard drive is a 160 GB stock unit.

It is interesting that you say the small 2.5" drive size is the reason the Mini is slower than your iMac. The newest 20" iMacs come with the 5400 RPM drives from laptop machines. One person on a forum was defending that choice by Apple saying that the more compact drive made it faster when reading files. I was complaining that Apple is making their machines cheaply by using laptop drives in a desktop machine and charging higher prices for them.

The idea of upgrading to an SSD is tempting but since this machine has the intel integrated GMA X3100 graphics that totally stink, I won't do it. My 2009 HP with the lowly GeForce 210 graphics card just zooms through photos and movies compared to the Apple. I would do better buying a used two year old machine with the newer chips.

After using your mini for a while, do you get page outs (Activity monitor -> System Memory).

BTW, the fact that you ran OnyX in the past an everything checked out, doesn't mean much. Caches, logs etc. could have built up sine then.
Check everything under the "Automation" tab and let it do it's thing.

Sometimes I see page outs and at other times it is zero. What does that mean?

If you see page outs it means you do not have enough RAM. Information wanted to stay in RAM, but you did not have enough, so it was swapped over to the hard drive to make room for other data in RAM. This is a slow process and typically you are looking at the beachball while this is taking place.

If page outs is more that 10% of page ins. Then I would get more RAM. If it's less than 10% I would live with it.

The numbers in your page in/page out get reset to zero when you reboot, so the computer must be running for some time to get value from the data.

eg.
Right now I have 5.0GB of page ins and 0 GB of page outs. I'm fine.
If I had 5.0GB of page ins and 1.0GB of page out, I'd buy more RAM.
If I have 500MB of page out, I'd live with it.

My Macbook Pro is a 2.4 Ghz with 2GB Ram and its also slower than my 2.0Ghz iMac. iMac has 4GB and the MBP only 2GB with Tiger, Leopard and Snow Leopard I think the faster CPU of the MBP just had the edge the iMac. Since Lion and Mountain Lion I would say the iMAc is the quicker system. Nothing changed but the MBP now feels slower. I think 2GB is on the limit for Lion & Mountain Lion and 4GB would speed it up.

You also mentioned you only have 2GB so I'd be looking at upping the ram_________________Phil